1. Field of the Invention
The present invention relates to a method for computing the quantity of injected fuel for an automobile engine equipped with an electronically controlled fuel injection system and an apparatus for detecting an exchange period for lubricating oils and constitutional parts, which are capable of informing an exchange period for an engine oil to a driver per use of a proper fuel quantity by calculating a total of the accumulated quantity of injected fuel for the automobile engine equipped with the electronically controlled fuel injection system, which are capable of informing the exchange period for various lubricating oils and constitutional parts to the driver in accordance with the number of exchange of the engine oil, which are capable of allowing the driver to exchange various lubricating oils and constitutional parts on a basis of accurate information under in an optimum condition, which are capable of preventing the driver from being confused, and which extend the life span of the automobile engine.
2. Description of the Prior Art
Generally, an engine oil of an automobile functions to reduce a friction and an abrasion occurred at an engine lubricating part and functions as a cooling agent, a clean agent, a sealing agent, a stress dispersing agent and so on. When an engine of the automobile is operated, an air-fuel mixture is burnt in a combustion chamber under a high temperature and thereby the oxidation and the carbonization are occurred therein. The friction and the abrasion of constitutional parts are also occurred in an engine room of the automobile. At this time, if the quantity of additives to be charged into the combustion chamber decreases or foreign materials such as a fuel oil, a moisture and so on are charged into the combustion chamber, the viscosity of an engine oil may decrease or may be increased.
When the viscosity of the engine oil decreases below a predetermined value, a power of engine may deteriorate or the automobile engine may be damaged due to the abrasion between metal surfaces of the constitutional parts. Consequently, the power of engine gets lost and the automobile engine may be broke down due to overheat of the engine.
Therefore, the engine oil must be periodically replaced. Referring to a consolidating guide distributed from an automobile manufacturer, an exchange period for the engine oil of the automobile is set to a driving state that the automobile has been traveled about 10,000 km. According to the consolidating guide, when a driver drives the automobile under severe operating condition, then he or she must exchange the engine oil of the automobile after driving the automobile by a short distance of 5,000 km.
Nevertheless, some driver, which is corresponding to 10% of the total drivers, may exchange the engine oil after driving the automobile by a very short distance of 3,000 km on a car mechanic's advice. Advices of the consolidating guide or the car mechanic are variables considered in determining whether the engine oil must be exchanged or not. An advice of a television broadcast is also variable considered in determining whether the engine oil must be exchanged or not. Accordingly, most of drivers are confused with respect to the exchange period for the engine oil.
Since there is no accurate guide for exchanging the engine oil, most of drives may determine the exchange period for the engine oil on a basis of vehicle-traveled distance. A variety of systems for informing the exchange period for various oils in a motor vehicle to a driver on a basis of vehicle-traveled distance have been proposed.
These systems are disclosed in Korean Patent Registered No. 240699(Date of Registration: Oct. 29, 1999), Korean Patent Laid-Open Publication No. 10-1998-47174(Date of Publication: Sep. 15, 1998) and Korean Utility Model Laid-Open Publication No. 20-1999-2105(Date of Publication: Jan. 15, 1999). These systems add up and compute the traveled distance of a motor vehicle and generate an alarm signal and make an on-and-off light operate so as to inform the exchange period for various oils in the motor vehicle to a driver when the accumulated distances approach to a threshold distance value.
Even these system inform the exchange period for various oils in the motor vehicle to the driver on a basis of the traveled distance, it has not been possible or practical to exactly inform the exchange period for the engine oil or the constitutional parts due to difference of running time of the automobile's engine. In other words, most of motor vehicles may be traveled in an area within the city limits at 25 km per hour and on the highway at 80˜110 km per hour. The running time of the motor vehicle's engine on the highway is about 4˜6 times greater than that of the motor vehicle's engine on the area within the city limits. Also, the fuel efficiency of the motor vehicle's engine on the highway is about 2˜3 times greater than that of the motor vehicle's engine on the area within the city limits. Since the running time and the fuel efficiency of the motor vehicle are variables considered in determining of exchange the engine oil and the constitutional parts, it has not been possible or practical to exactly inform the exchange period for the engine oil or the constitutional parts.